"I did a lot of my own prepping," the "Wide Awake" singer, 28, said of the cover that was shot on a farm in Upstate New York. "I kind of went on a cleanse, I did a lot of stuff like vitamins and supplements, I changed my coffee to green tea, I didn't drink alcohol for three months."

"I was really in the zone, I just wanted to be glowing for that cover," she continued.

Indeed, in May, John Mayer's current girl showed off various supplements she was taking in a Twitter picture. "I'm all the about that supplement & vitamin LYFE," she wrote with the pic.

Despite the regimen, Perry seemed pleased with the end result -- sharing how "amazing" it was to work with Leibovitz. "She's incredible," she said. "It was really fantastic working with her … She [has] such a great vibe, she's got no ego which is fantastic, and she really let's me be creative as well."

Perry, who voices Smurfette in the upcoming July 31 Smurfs 2 movie, also opened up about the vibe of her upcoming album, which she said will debut "soon."